Day 0 exploit regarding unit tags

[H-Park]

The difference of IDs between sequentially created units, regardless of which player created them, is 262144 (for probes) plus/minus 2. This can be used to determine how many units your opponent has created since you last created a unit, which can be used to detect ling rushes and among other things.

Proposed fix: have the protocol make a mapping between real unit id and a random tag, then interchange them where appropriate.

See discussion on the discord regarding this.